RDP Customer Document
Technical Manual
APPLICATION DETAILS FOR THE RL
RANGE OF LOAD CELLS
Doc. Ref CD1060C
BS EN ISO 9001
Certificate No. FM13141
All other countries
USA & Canada
RDP Electrosense Inc.
RDP Electronics Ltd
2216 Pottstown Pike
Pottstown, PA 19465
U.S.A.
Tel (610) 469-0850
Fax (610) 469-0852
E-mail info@rdpe.com
www.rdpe.com
Grove Street, Heath Town,
Wolverhampton, WV10 0PY
United Kingdom
Tel: +44 (0) 1902 457512
Fax: +44 (0) 1902 452000
E-mail: sales@rdpe.com
www.rdpe.com
APPLICATION DETAILS FOR THE RL RANGE OF LOAD CELLS
For general handling and installation application notes refer to customer document
CD1039.
The RL range comprises flat ‘pancake’ (compression and universal) load cells, and beam
load cells for weighing and force measurement applications.
1.
Summary of models in the RL range
Model
Type
Ranges
(kg)
Material
Sealing
Nominal
Bridge
Resistance
(ohms)
RLC
Compression
100 to 50,000
Tool steel
IP65
350/700
RLT
Tension
5 to 2,500
Tool steel
IP65
350
RLW
Weighing
10 to 1,500
Tool steel
IP67
350
RLS
Single point weighing
10 to 100
Aluminium
Alloy
IP65
350
RLU
Tension/compression
100 to 10,000
Tool steel
IP65
350/700
2.
The materials used in the construction of the load cells are shown in the table
above. As an option it is possible to replace the tool steel with stainless steel.
3.
The nominal bridge resistances given (see table above) are for the output (greenwhite cable cores). The tolerance is less than ± 10 ohm. The input resistance is
slightly higher – typically 385 ± 30 ohms for nominal 350 ohm bridges and 750 ±30
ohms for nominal 700 ohm bridge.
4.
The sensitivity (all models) is 2 mV/V FS ±10% eg at 10 volts excitation the full load
output will be 20 mV ± 10%.
5.
The safe overload capacity is 150% FS (all models) and the ultimate overload
capacity is 200% FS.
6.
Insulation resistance: >=1000MΩ at 50VDC (all models).
7.
Performance:
Parameter
Non-linearity (max)
Hysteresis (max)
Non-repeatability (max)
Percentage of full range
Models U, C, T, W
Model S
±0.03%
±0.03%
±0.03%
±0.02%
±0.02%
±0.02%
8.
Environmental (all models):
Operating temperature range:
Compensated temperature range:
Temperature
Coefficients
Zero (max)
Span (max)
9.
-20 to +60°C
-10 to +40°C
U,C
% FS per °C
±0.002
±0.002
Models
S
% FS per °C
±0.0025
±0.0025
T, W
% FS per °C
±0.003
±0.003
Electrical connection:
Each load cell is fitted with an integral 3 metre long four core screened cable. The
screen is not connected to the load cell body. The load cell body will normally be
grounded via the mounting metalwork. The cable screen should be connected to
the instrument.
The cable cores are:
Core Colour
Red
Black
Green
White
excitation positive
excitation negative
output positive
output negative
Connection diagrams showing RL connections to various RDP instruments are:
10.
11.
Diagram
Instrument
Diagram
Instrument
D17031
D17033
D17034
D17889
E308
S7DC
S7MZ
DR7DC
D17036
D17035
D17037
TR150
611
E725-DC1
Outline Drawings:
Drawing
Load cell model
D16999
D17000
D17002
D17003
D16846
RLC
RLT
RLW
RLS
RLU
Calibration
Each load cell is individually calibrated with equipment traceable to national
standards, and an individual sensitivity figure is given.
RDP offers a calibration service when a load cell and instrument are purchased
together. The instrument set-up to read the load/force in units specified by the
customer.
WARRANTY AND SERVICE
WARRANTY.
R.D.P. Electronics products are warranted against defects in materials or workmanship.
This warranty applies for one year from the date of delivery. We will repair or replace
products that prove to be defective during the warranty period provided they are returned
to R.D.P. Electronics.
This warranty is in lieu of all other warranties, expressed or implied, including the implied
warranty of fitness for a particular purpose to the original purchaser or to any other person.
R.D.P. Electronics shall not be liable for consequential damages of any kind.
If the instrument is to be returned to R.D.P. Electronics for repair under warranty, it is
essential that the type and serial number be quoted, together with full details of any fault.
SERVICE.
We maintain comprehensive after-sales facilities and the instrument can, if necessary be
returned to our factory for servicing.
Equipment returned to us for servicing, other than under warranty, must be accompanied
by an official order as all repairs and investigations are subject to at least the minimum
charge prevailing at the date of return.
The type and serial number of the instrument should always be quoted, together with full
details of any fault and services required.
IMPORTANT NOTES.
1.
No service work should be undertaken by the customer while the unit is under
warranty except with the authorisation of RDP Electronics.
2.
If the instrument is to be returned to R.D.P. Electronics for repair, (including repair
under warranty) it is essential that it is suitably packed and that carriage is insured
and prepaid. R.D.P. Electronics can accept no liability whatsoever for damage
sustained during transit.
3.
It is regretted that the above warranty only covers repairs carried out at our factory.
Should the instrument have been incorporated into other equipment that requires
our engineers to perform the repair on site, a charge will be made for the engineer's
time to and from the site, plus any expenses incurred.
The aforementioned provisions do not extend the original warranty period of any product
that has been either repaired or replaced by R.D.P. Electronics.
THIS WARRANTY MAY BE NULL AND VOID SHOULD
THE CUSTOMER FAIL TO MEET OUR TERMS OF PAYMENT.